JP7383237B2 - Laminate and decorative sheet using the same - Google Patents

Description

The present invention relates to a resin laminate such as a resin film, and a decorative sheet using the same for use in building interior materials, building exterior members such as entrance doors, the surfaces of fittings, the surface materials of home appliances, and the like.

In recent years, many decorative sheets using olefin resins have been proposed as decorative sheets to replace vinyl chloride decorative sheets. These decorative sheets are used to protect interior materials of houses and public facilities, exterior materials such as entrance doors, surfaces of fittings, and surface materials of home appliances. Therefore, they are exposed to direct sunlight, wind and rain every day, and extremely high weather resistance is required. (See Patent Document 1)
The decorative sheets described in Patent Document 1 all incorporate light stabilizers, ultraviolet absorbers, and the like into protective layers and coating layers to improve weather resistance. However, with long-term use, the light stabilizer and ultraviolet absorber may disappear due to bleed-out from the olefin resin or coating surface, or the chemical structure of each material may be destroyed by oxygen or light, causing the function to disappear. It has been known.

Patent No. 4032829

However, if a target layer such as a protective layer or a coating layer contains an amount of UV absorber or light stabilizer that provides sufficient weather resistance, the UV absorber or light stabilizer will be added to the resin composition constituting each layer. Agglomeration of stabilizer may occur.
Furthermore, the chemical structure of the UV absorber and light stabilizer in the resin composition is broken and the molecules are reduced, resulting in so-called bleed-out, where the decomposed components of the UV absorber and light stabilizer stand out from the surface of each layer. It is more likely to occur. Then, the adhesion with other layers may deteriorate, or it may stand out on the surface layer, causing problems such as stickiness.

The present invention has been made with attention to the above-mentioned points, and an object of the present invention is to provide a decorative sheet having stable weather resistance.

The present inventors have investigated various conditions to prevent the decomposition of ultraviolet absorbers and light stabilizers over time and to enable them to be used over a long period of time without deteriorating quality, and have determined suitable conditions for the top coat layer. I found it.
In order to solve the problem, a laminate of one embodiment of the present invention is a laminate including a plurality of resin layers, and a top coat layer located on the outermost surface side of the laminate has a pKa of 4.0 to 4.0. It is characterized by containing 7.0 of a light stabilizer.

According to one aspect of the present invention, by using the above laminate, it is possible to provide a decorative sheet that has stable weather resistance over a long period of time.

FIG. 1 is a cross-sectional view illustrating a laminate according to an embodiment of the present invention.

Embodiments of the present invention will be described with reference to the drawings.
Here, the configuration shown in FIG. 1 is a schematic one, and the relationship between the thickness and the planar dimension, the ratio of the thickness of each layer, etc. are different from the actual configuration. In addition, the embodiments shown below illustrate configurations for embodying the technical idea of the present invention, and the technical idea of the present invention is that the materials, shapes, structures, etc. of the component parts are It is not limited to things. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims.

As shown in FIG. 1, the decorative sheet 1 of this embodiment has an ink layer 5, an adhesive layer 4, a transparent resin layer 3 as a surface protection layer, and a top coat on a raw fabric layer 6 constituting a base material layer. The layers 2 are arranged in this order. An embossed pattern 3a constituting an uneven pattern is formed on the upper surface of the transparent resin layer 3. The uneven pattern may be formed by a method other than embossing. The transparent resin layer 3 is composed of an olefin resin layer. In the example of FIG. 1, the adhesive resin layer 7 is provided between the transparent resin layer 3 and the adhesive layer 4 in order to improve adhesiveness, but the adhesive resin layer 7 is not provided. Also good.

This decorative sheet 1 is made, for example, by forming an adhesive layer 4 on a raw resin sheet in which an ink layer 5 is formed on one side of a raw fabric layer 6 to form a first laminate, and a transparent resin layer. A top coat layer 2 containing a light stabilizer and a gloss modifier is formed on a resin sheet obtained by co-pressing 3 and an adhesive resin layer 7 to form a second laminate. It is manufactured by bonding a laminate using dry lamination or extrusion lamination.
Details of each layer will be explained below.

<Top coat layer>
A top coat layer 2 is provided on the outermost layer of the decorative sheet 1, which serves to protect the surface and adjust gloss. The top coat layer 2 contains at least a light stabilizer. It is preferable that the top coat layer 2 contains an ultraviolet absorber in addition to a light stabilizer.
Furthermore, the top coat layer 2 of this embodiment contains inorganic particles as a gloss modifier.

Here, although FIG. 1 illustrates a case where the top coat layer 2 is formed along the surface of the transparent resin layer 3 over the entire surface of the transparent resin layer 3, the present invention is not limited thereto. The top coat layer 2 is formed by applying a resin composition to the recesses of the embossed pattern 3a formed on the transparent resin layer 3, and embedding the resin composition only in the recesses by scraping off the coating liquid with a squeegee or the like. It may be buried and provided by wiping. Further, the surface of the top coat layer 2 may be flat regardless of the recesses of the embossed pattern 3a. The top coat layer 2 only needs to be provided so as to be embedded in at least the recesses of the embossed pattern 3a, and even in the recesses where the layer thickness is reduced by forming the embossed pattern 3a, the buried top coat layer 2 Can maintain high weather resistance. Note that by providing the top coat layer 2 so as to cover the entire surface of the transparent resin layer 3, it is possible to provide the decorative sheet 1 with better weather resistance.

(resin material)
The resin material as the main component of the top coat layer 2 is appropriately selected from polyurethane-based, acrylic silicone-based, fluorine-based, epoxy-based, vinyl-based, polyester-based, melamine-based, aminoalkyd-based, urea-based, and other resin materials. Can be used. The form of the resin material is not particularly limited, and may be water-based, emulsion, solvent-based, or the like. The curing method can be appropriately selected from one-liquid type, two-liquid type, ultraviolet curing method, etc.
Here, the main component in this specification refers to a resin material that is contained in 70% by mass or more, preferably 90% by mass or more of the material constituting the target layer.

As the resin material used as the main component of the top coat layer 2, a urethane-based resin material using isocyanate is preferable from the viewpoints of workability, price, cohesive force of the resin itself, and the like. Isocyanates include tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI), diphenylmethane diisocyanate (MDI), lysine diisocyanate (LDI), isophorone diisocyanate (IPDI), bis(isocyanatemethyl)cyclohexane ( HXDI), trimethylhexamethylene diisocyanate (TMDI) and other derivatives such as adducts, burettes, isocyanurates, and other curing agents can be selected as appropriate, but in consideration of weather resistance, linear molecules Curing agents based on hexamethylene diisocyanate (HMDI) or isophorone diisocyanate (IPDI) with the structure are suitable.

In addition, in order to improve the surface hardness, it is preferable to use a resin that is cured by active energy rays such as ultraviolet rays and electron beams. Known materials such as various monomers and commercially available oligomers can be used as the main materials, including pentaerythritol triacrylate (PET3A), pentaerythritol tetraacrylate (PET4A), trimethylolpropane triacrylate (TMPTA), It is preferable to use a polyfunctional monomer such as dipentaerythritol hexaacrylate (DPHA), a polyfunctional oligomer such as Shiko UV-1700B (manufactured by Nippon Gosei Kagaku), or a mixture thereof.

Note that these resins can be used in combination with each other; for example, a hybrid type of thermosetting type and photocuring type can be used to improve surface hardness, suppress curing shrinkage, and improve adhesion. can be achieved.
Further, at this time, the top coat layer 2 is composed of a plurality of layers, for example, a thermosetting layer mainly composed of a thermosetting resin, and a photocuring layer mainly containing a photocuring resin such as an ultraviolet curable resin. It's okay. By configuring the decorative sheet 1 from two hardened layers in this way, the surface hardness of the decorative sheet 1 can be improved. At this time, it is preferable that the photocured layer is on the surface layer side.

(light stabilizer)
In this embodiment, the top coat layer 2 contains a light stabilizer having a pKa of 4.0 or more and 7.0 or less. Here, when the top coat layer 2 is a plurality of layers, it is preferable that each layer contains a light stabilizer having a pKa of 4.0 or more and 7.0 or less, but at least One layer may contain a light stabilizer having a pKa of 4.0 or more and 7.0 or less.
The light stabilizer is preferably a hindered amine light stabilizer. In particular, a hindered amine light stabilizer having an aminoether group and a molecular weight of 600 or more is more preferable. The molecular weight of the light stabilizer may be measured, for example, by number average molecular weight.

Although the method for measuring the number average molecular weight of the above-mentioned light stabilizer is not particularly limited, it is preferable to use gel permeation chromatography. Although the GPC measuring device is not particularly limited, polystyrene gel is preferably used as the packing material for the GPC column, and tetrahydrofuran (THF) is preferably used as the eluent. Moreover, polystyrene polymer may be used as a standard substance for GPC.
However, when the above-mentioned light stabilizer is constituted by a single substance and its structure is known, the value calculated from the structural formula may be used as the molecular weight of the light stabilizer.
The light stabilizer is, for example, the following hindered amine compound (1), and the hindered amine compound described above can capture radicals by the reaction of reaction formula (2).

Examples of hindered amine light stabilizers include bis(2,2,6,6-tetramethylpiperidin-4-yl)sebacate; bis(2,2,6,6-tetramethylpiperidin-4-yl)succinate; bis( 1,2,2,6,6-pentamethylpiperidin-4-yl) sebacate; bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate; bis(1,2 ,2,6,6-pentamethylpiperidin-4-yl) n-butyl 3,5-di-tert-butyl 4-hydroxybenzyl malonate; 1-(2-hydroxyethyl)-2,2,6,6 -Condensation product of tetramethyl-4-hydroxypiperidine and succinic acid; 2,2,6,6-tetramethylpiperidin-4-yl stearate; 2,2,6,6-tetramethylpiperidin-4-yldodecanate ;1,2,2,6,6-pentamethylpiperidin-4-yl stearate;1,2,2,6,6-pentamethylpiperidin-4-yldodecanate;N,N'-bis(2, Tris(2,2,6, 6-tetramethylpiperidin-4-yl) nitrilotriacetate; Tetrakis(2,2,6,6-tetramethylpiperidin-4-yl)-1,2,3,4-butanetetracarboxylate; 4-benzoyl-2 ,2,6,6-tetramethylpiperidine; 4-stearyloxy-2,2,6,6-tetramethylpiperidine; bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl 2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonic acid; 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5] Decane-2,4-dione; bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl) sebacate; bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl) succinate; Condensate of N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-morpholino2,6-dichloro-1,3,5-triazine; 2-chloro Condensation of -4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane 2-chloro-4,6-bis(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis-(3 -Aminopropylamino)ethane condensate; 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione; 3 -dodecyl-1-(2,2,6,6-tetramethylpiperidin-4-yl)pyrrolidine-2,5-dione; 3-dodecyl-1-(1-ethanoyl-2,2,6,6-tetra Methylpiperidin-4-yl)pyrrolidine-2,5-dione; 3-dodecyl-1-(1,2,2,6,6-pentamethylpiperidin-4-yl)pyrrolidine-2,5-dione; 4- Mixture of hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine; N,N'-bis(2,2,6,6-tetramethylpiperidin-4-yl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine condensate; 1,2-bis(3-aminopropylamino)ethane, 2,4,6-trichloro-1,3,5 -Condensation product of triazine and 4-butylamino-2,2,6,6-tetramethylpiperidine; 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4- Oxospiro[4.5]decane; Oxo-piperandinyl-triazine; 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro[4.5]decane and reaction products of epichlorohydrin.

In addition, as an N-alkoxy hindered amine light stabilizer, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate; -Butanetetracarboxylic acid tetrakis(1,2,2,6,6-pentamethyl-4-piperidinyl) ester; 1,2,3,4-butanetetracarboxylic acid 1,2,2,6,6-pentamethyl-4 -Piperidinyltridecyl ester; 1,2,3,4-butanetetracarboxylic acid 2,2,6,6-tetramethyl-4-piperidinyltridecyl ester; 1,2,3,4-butanetetracarboxylic acid and 1,2,2,6,6-pentamethyl of a polymer of 2,2,6,6-tetramethyl-2,4,8,10-tetraoxaspiro[5.5]-undecane-3,9-diethanol -4-piperidinyl ester; 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-2,4,8,10-tetraoxaspiro[5.5]-undecane 3 , 2,2,6,6-tetramethyl-4-piperidinyl ester of polymer of 9-diethanol; bis(1-undecaneoxy-2,2,6,6-tetramethylpiperidin-4-yl) carbonate, etc. can be mentioned.

In addition, as hydroxyl-substituted N-alkoxy HALS, 1-(2-hydroxy-2-methylpropoxy)-2,2,6,6-tetramethyl-4-piperidinol; 1-(2-hydroxy-2-methylpropoxy) -4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine; 1-(4-octadecanoyloxy-2,2,6,6-tetramethylpiperidin-1-yloxy)-2-octa Decanoyloxy-2-methylpropane; 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol; 1-(2-hydroxyethyl)-2,2,6,6- Examples include reaction products of tetramethyl-4-piperidinol and dimethyl succinate.

Among these hindered amine light stabilizers, typical commercially available ones include Tinuvin 123, Tinuvin 152, Tinuvin NOR 371 FF, Tinuvin XT850 FF, Tinuvin XT855 FF, and TINUVIN 510 manufactured by BASF Japan Co., Ltd. 0 , TINUVIN 622SF, Flamestab NOR 116 FF, and ADEKA STAB LA-81 manufactured by ADEKA Corporation. These may be used alone or in combination of two or more.
When a light stabilizer is blended into the top coat layer 2, it is preferably blended from 0.1 parts by mass to 5.0 parts by mass with respect to 100 parts by mass of the resin of the layer to be blended. More preferably, it is 0.3 parts by mass or more and 3.0 parts by mass or less. If the amount of the light stabilizer is less than 0.1 parts by mass, the effect of stabilizing the resin against generated radicals may be low. On the other hand, if the amount is more than 5.0 parts by mass, there is a high possibility that bleed-out will occur.

(Ultraviolet absorber)
When adding an ultraviolet absorber to the top coat layer 2, it is preferable to add an ultraviolet absorber having a pKa of -4.5 to -5.5 when irradiated with light. Here, when the top coat layer 2 has a plurality of layers, it is preferable that each layer contains an ultraviolet absorber having a pKa of -4.5 to -5.5 when irradiated with light.
When blending an ultraviolet absorber into the top coat layer 2, it is preferably blended in a range of 1.0 parts by mass or more and 15.0 parts by mass or less, based on 100 parts by mass of the resin of the layer to be blended. More preferably, it is 2.5 parts by mass or more and 8.0 parts by mass or less. If the amount of the ultraviolet absorber is less than 1.0 part by mass, the effect of stabilizing the resin against ultraviolet rays may be low. On the other hand, if the amount is more than 15.0 parts by mass, there is a high possibility that bleed-out will occur.

In addition, when the top coat layer 2 has a thermosetting layer and a photocuring layer as described above, it is preferable to mix a relatively large amount of the above-mentioned ultraviolet absorber on the thermosetting layer side.
The ultraviolet absorber can be selected from at least one of benzotriazole, triazine, benzophenone, benzoate, and cyanoacrylate.
In particular, benzotriazole-based or triazine-based organic ultraviolet absorbers have high ultraviolet absorption ability and are excellent in heat resistance, volatility resistance, and resin compatibility, so it is preferable to select and use at least one of them. Further, the ultraviolet absorber preferably has a triazine skeleton or a benzotriazole skeleton and has a molecular weight of 400 or more. The molecular weight of the ultraviolet absorber may be calculated from its structural formula, or may be the number average molecular weight measured by a known method.

The ultraviolet absorber is a compound (3) having a hydroxyphenyltriazine skeleton or a compound (4) having a benzotriazole skeleton described below, and these are preferably compounds having maximum absorption in the range from 270 nm to 400 nm. The above-mentioned ultraviolet absorbers are excited by absorbing light, and hydrogen atoms move within the molecule depending on the skeleton. It can return to the ground state by releasing heat. These can be shown by reaction formula (5) and reaction formula (6), respectively.

Examples of compounds having the above-mentioned hydroxyphenyltriazine skeleton include 2-(2-hydroxy-4-octoxyphenyl)-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-(2- Hydroxy-4-hexyloxyphenyl)-4,6-diphenyl-s-triazine, 2-(2-hydroxy-4-propoxy-5-methylphenyl)-4,6-bis(2,4-dimethylphenyl)- s-triazine, 2-[2-hydroxy-4-(3-dodecyloxy-2-hydroxypropyloxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-[2 -Hydroxy-4-(3-tridecyloxy-2-hydroxypropyloxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-[2-hydroxy-4-[3 -(2-ethylhexyloxy)-2-hydroxypropyloxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-s-triazine, 2-(2-hydroxy-4-hexyloxyphenyl)-4 ,6-Dibiphenyl-s-triazine, 2-[2-hydroxy-4-[1-(i-octyloxycarbonyl)ethyloxy]phenyl]-4,6-diviphenyl-s-triazine, 2,4-bis (2-hydroxy-4-octoxyphenyl)-6-(2,4-dimethylphenyl)-s-triazine, 2,4-bis(4-butoxy-2-hydroxyphenyl)-6-(2,4- dibutoxyphenyl)-s-triazine, 2,4,6-tris(2-hydroxy-4-octoxyphenyl)-s-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2 -Hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine (trade name CYASORB (registered trademark) UV-1164), 2,4,6-tris(2-hydroxy-4-hexyloxy-3 -methylphenyl)-1,3,5-triazine (trade name LA-F70).

Examples of the compounds having the benzotriazole skeleton include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)- 5-chlorobenzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-(2-(octyloxycarbonyl)ethyl)phenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy -3'-dodecyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole, 2-(2'-hydroxy -5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-(dimethylbenzyl)phenyl)benzotriazole, 2-(2'-hydroxy-4'-octyloxy) phenyl)benzotriazole, 2,2'-methylene-bis(2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-3'-(3,4,5 , 6-tetrahydrophthalimidylmethyl)-5'-methylbenzyl)phenyl)benzotriazole, 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol (product) LA-36), 2-(5-chloro-2-benzotriazolyl)-6-tert-butyl-p-cresol (trade name tinuvin (registered trademark) 326), and the like.

Benzotriazole-based UV absorbers include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)benzo Triazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tertiary octylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-dicumylphenyl)benzotriazole, 2,2 Examples include '-methylenebis(4-tert-octyl-6-benzotriazolyl)phenol.

Triazine-based UV absorbers include 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine, 2 -[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4 -bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-tridecyloxypropyl) )oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-[(2-hydroxy-3-(2'-ethyl) )hexyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine.

Benzophenone-based UV absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 5,5'-methylenebis(2-hydroxy-4-methoxybenzophenone). ), etc.
Examples of benzoate-based ultraviolet absorbers include phenyl salicylate, resorcinol monobenzoate, 2,4-di-tert-butylphenyl-3',5'-di-tert-butyl-4'-hydroxybenzoate, and 2,4-di-tert-butyl phenyl-3',5'-di-tert-butyl-4'-hydroxybenzoate. Examples include amyl phenyl-3',5'-di-tert-butyl-4'-hydroxybenzoate and hexadecyl-3,5-di-tert-butyl-4-hydroxybenzoate.
Examples of cyanoacrylate-based ultraviolet absorbers include ethyl-α-cyano-β,β-diphenylacrylate and methyl-2-cyano-3-methyl-3-(p-methoxyphenyl)acrylate.

(Gloss adjuster)
Top coat layer 2 contains inorganic particles as a gloss modifier. Examples of inorganic particles include silica, clay, calcium carbonate, barium sulfate, alumina white, aluminum hydroxide, talc, bentonite, titanium oxide, and anhydrous silicic acid known as colloidal silica, hydrated silicic acid, and hydrated calcium silicate. , white carbon such as hydrous aluminum silicate, and alumina sol. Further, it is preferable to modify the surface with polydimethylsiloxane, polyethylene wax, surfactant, etc. because it improves dispersibility and stain resistance.

The particle diameter of the inorganic particles is preferably 1 μm or more and 20 μm or less. More preferably, it is 3 μm or more and 10 μm or less. If the particle size is smaller than 1 μm, the gloss adjustment effect may be low. On the other hand, if it is larger than 20 μm, there is a high possibility that the filler will be missing from the coat surface.
The pH of the inorganic particles to be blended is desirably in the vicinity of neutrality, greater than 5.0 and less than 8.5. If inorganic particles having a pH of 5.0 or less or greater than 8.5 are used, by-products may be produced depending on the pKa of the light stabilizer.
The above-mentioned inorganic particles contribute to the design (gloss) of the decorative sheet, so they are blended (added) in an appropriate amount. The amount of inorganic particles to be blended may be 1 part by mass or more and 20 parts by mass or less based on 100 parts by mass of the resin, which is the main component of the top coat layer 2.

<Transparent resin layer>
The transparent resin layer 3 constitutes the base material of the top coat layer 2, and when the ink layer 5 is provided, it becomes a protective layer that protects the ink layer 5. The transparency of the transparent resin layer 3 may be such that the ink layer 5 is visible. Note that the laminate only needs to include at least the transparent resin layer 3 and the top coat layer 2. When the ink layer 5 is not provided, the transparent resin layer 3 does not need to be transparent.
The transparent resin layer 3 is preferably a resin layer whose main component is an olefin resin and contains 0.3 parts by mass or more of a compound having a pKa of 7.0 or less based on 100 parts by mass of the resin material. The amount of the compound having a pKa of 7.0 or less to be blended is preferably 15.0 parts by mass or less.
The compound having a pKa of 7.0 or less is, for example, the same light stabilizer or ultraviolet absorber that is blended into the top coat layer 2 as described above.

In the transparent resin layer 3 of this embodiment, an embossed pattern is formed as shown in FIG.
The embossed pattern 3a is formed to improve the design. The embossed pattern 3a can be formed by applying heat and pressure using an embossing plate having an uneven pattern before forming the top coat layer 2, or by forming a film using an extruder. The embossed pattern 3a can be formed by a method in which the embossed pattern 3a is simultaneously formed while cooling the sheet using a cooling roll having an uneven pattern.

The resin material used as the main component of the transparent resin layer 3 is preferably made of olefin resin, and in addition to polypropylene, polyethylene, polybutene, etc., alpha olefins (for example, propylene, 1-butene, 1-pentene, 1 -Hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1 -nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4 -dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) alone Polymerization or copolymerization of two or more types, ethylene/vinyl acetate copolymer, ethylene/vinyl alcohol copolymer, ethylene/methyl methacrylate copolymer, ethylene/ethyl methacrylate copolymer, ethylene/butyl methacrylate copolymer Examples include copolymerization of ethylene or α-olefin with other monomers, such as ethylene/methyl acrylate copolymer, ethylene/ethyl acrylate copolymer, ethylene/butyl acrylate copolymer, etc. . Moreover, when aiming at improving the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene.

Note that the resin composition constituting the transparent resin layer 3 may contain various functionalities such as a heat stabilizer, a light stabilizer, an antiblocking agent, a catalyst scavenger, a coloring agent, a light scattering agent, and a gloss control agent, as necessary. Additives may also be included. These various functional additives can be appropriately selected from well-known ones and used.
When non-polar polypropylene is used for the transparent resin layer 3 and the adhesiveness between the transparent resin layer 3 and the resin layer disposed on the lower surface is low, it is preferable to provide the adhesive resin layer 7. The adhesive resin layer 7 is preferably acid-modified resin such as polypropylene, polyethylene, or acrylic, and the layer thickness is preferably 2 μm or more and 20 μm or less from the viewpoint of adhesiveness and heat resistance. Moreover, from the viewpoint of improving adhesive strength, the adhesive resin layer 7 is preferably formed with the transparent resin layer 3 by a coextrusion lamination method.

<Ink layer and adhesive layer>
On the lower surface side of the transparent resin layer 3, as shown in FIG. 1, an adhesive layer 4 is provided to further improve the adhesion between the ink layer 5 on the lower surface side and the transparent resin layer 3.
The material for the adhesive layer 4 is not particularly limited, but can be appropriately selected from acrylic, polyester, polyurethane, epoxy, and the like. The coating method can be selected as appropriate depending on the viscosity of the adhesive, etc., but generally, gravure coating is used, and the ink layer 5 is applied to the side of the original fabric layer 6 on which the ink layer 5 has been applied. Thereafter, it is laminated with a transparent resin layer 3 and an adhesive resin layer 7. Note that the adhesive layer 4 can be omitted if sufficient adhesive strength between the transparent resin layer 3 and the ink layer 5 can be obtained.

An ink layer 5 is provided on the lower surface side of the adhesive layer 4. It is preferable that the ink layer 5 contains at least a light stabilizer. As the light stabilizer, it is preferable to use a hindered amine material. By including a light stabilizer in the ink layer 5, the pigment fades due to the radicals generated due to deterioration of the binder resin itself forming the ink layer 5 or resins in other layers reducing the chemical components of the pigment in the ink. can be suppressed and maintain a vivid pattern for a long period of time.
The ink layer 5 of this embodiment includes a picture pattern layer 5a and a solid ink layer 5b. At least the picture pattern layer 5a contains a light stabilizer for the above-mentioned purpose. Further, by providing the solid ink layer 5b on the lower surface side of the picture pattern layer 5a, concealing properties can be provided.

For the ink of the picture pattern layer 5a, binders such as nitrified cotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyester, etc. may be used alone or appropriately selected from modified products thereof. can. The binder is not particularly limited to water-based, solvent-based, emulsion-based, etc., and the curing method may be a one-part type or a two-part type using a curing agent. Furthermore, a method of curing the ink by irradiation with active energy rays such as ultraviolet rays or electron beams may be used. In particular, a common method uses urethane-based ink, which is cured with isocyanate. In addition to these binders, the ink contains pigments, colorants such as dyes, extender pigments, solvents, various additives, etc. that are included in ordinary inks. Examples of highly versatile pigments include pearls such as condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and mica.

Basically, the same material as the ink used for the picture pattern layer 5a can be used for the solid ink layer 5b, but if the ink is a transparent material, opaque pigments, iron oxide, titanium oxide, etc. are used. be able to. In addition, it is also possible to provide concealing properties by adding metals such as silver, copper, and aluminum. Generally, aluminum flakes are used. Note that the solid ink layer 5b may not be provided.
These ink layers 5 can be formed directly on the original fabric layer 6 by gravure printing, offset printing, screen printing, flexographic printing, electrostatic printing, inkjet printing, or the like. Further, in the case of imparting concealing properties with metal, it is preferable to use a comma coater, a knife coater, a lip coater, metal vapor deposition, sputtering, or the like.
In addition, for the interface where the resin material or ink is laminated, in consideration of its adhesion, the surface to be laminated should be subjected to corona treatment, ozone treatment, plasma treatment, or electron beam treatment before applying the resin material or ink. The adhesion between the layers can be improved by activating the surface by subjecting it to a surface treatment such as UV light treatment, dichromic acid treatment, etc., and then performing a lamination process.

<Original fabric layer>
An original fabric layer 6 serving as a base material layer is provided on the lower surface side of the ink layer 5. The raw fabric layer 6 is made of paper such as tissue paper, titanium paper, or resin-impregnated paper, or synthetic resin such as polyethylene, polypropylene, polystyrene, polybutylene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, or acrylic. Foams of these synthetic resins, rubbers such as ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene-styrene block copolymer rubber, polyurethane, organic or inorganic nonwoven fabrics, synthetic paper, aluminum, It can be arbitrarily selected from metal foils such as iron, gold, and silver.

In addition, when an olefin resin is used as the raw fabric layer 6, the surface is often in an inactive state, so a base material (not shown) to which the raw fabric layer 6 and the decorative sheet 1 are attached is used. It is preferable to provide a primer layer (not shown) between them. In addition, in order to improve the adhesion between the raw fabric layer 6 made of olefin resin and the above-mentioned base material, the back surface of the raw fabric layer 6 is subjected to corona treatment, plasma treatment, ozone treatment, and electron beam treatment. , ultraviolet ray treatment, dichromic acid treatment, or the like.
Note that the same material as the ink layer 5 can be used as the primer layer, but considering that the decorative sheet 1 is wound up in the form of a web, it is necessary to avoid blocking and to improve adhesion with the adhesive. It is preferable to contain an inorganic filler such as silica, alumina, magnesia, titanium oxide or barium sulfate.
In the decorative sheet 1 of this embodiment, the raw fabric layer 6 has a thickness of 20 μm to 150 μm, the adhesive layer 4 has a thickness of 1 μm to 20 μm, the transparent resin layer 3 has a thickness of 20 μm to 200 μm, and the top coat layer 2 is preferably 3 μm to 20 μm, and the total thickness of the decorative sheet 1 is preferably within the range of 45 μm to 400 μm.

<About other effects>
Since the ultraviolet absorber and the light stabilizer require intermolecular interaction, it is preferable that they be present in close proximity. Here, we will look at the interaction when using a UV absorber with a triazine skeleton or benzotriazole skeleton and a light stabilizer with a hindered amine skeleton. In general, intermolecular interaction between a UV absorber and a light stabilizer occurs between the conjugated system of the UV absorber and the hindered amine skeleton of the light stabilizer. There is a high probability that the ultraviolet absorber has an intramolecular hydrogen bond formed on the nitrogen of the triazine skeleton or benzotriazole skeleton when it absorbs light. In other words, hydrogen on the hydroxyl group is in a state where it is easy to dissociate.

By allowing a light stabilizer with a pKa larger than 7.0 to coexist, the ultraviolet absorber that absorbs light and is in an excited state tends to undergo a side reaction through an acid-base reaction with the light stabilizer. In other words, the ultraviolet absorber and the light stabilizer cannot undergo the reactions of Reaction Formula (2), Reaction Formula (5) and Reaction Formula (6) that originally occur, resulting in an increase in side reactions. In other words, it becomes easily decomposed by light, leading to a decrease in weather resistance. On the other hand, when using a photostabilizer with a pKa of 7.0 or less, it is difficult to cause an acid-base reaction with hydrogen on the hydroxyl group of the ultraviolet absorber, which absorbs light and is in an excited state. The agent easily undergoes the reactions of Reaction Formula (2), Reaction Formula (5) and Reaction Formula (6). Therefore, weather resistance against light can be improved.

In view of this, in this embodiment, a light stabilizer with a pKa of 4.0 to 7.0 is blended into the resin composition constituting the top coat layer 2, thereby providing a stable coating for a long period of time. A weather-resistant laminate or decorative sheet 1 can be provided.
Further, as in the present embodiment, by containing a light stabilizer having a pKa of 4.0 to 7.0 in the resin composition of the top coat layer 2, an inorganic material as a gloss modifier can be added to the top coat layer 2. By incorporating particles, it is possible to prevent a decrease in weather resistance. This is because when the pKa of the light stabilizer is larger than 7.0, side reactions are likely to occur in the vicinity of the top coat layer 2 in contact with the inorganic particle surface due to acid-base reactions, and the light stabilizer in the top coat layer 2 This is because the ratio of Therefore, as the light stabilizer to be added to the top coat layer 2, it is preferable to use a light stabilizer having a pKa of 7.0 or less.

Furthermore, as in the present embodiment, by containing a light stabilizer having a pKa of 4.0 to 7.0 in the resin composition of the top coat layer 2, residual monomers derived from the raw materials can be contained in the top coat layer 2. etc., it is possible to prevent a decrease in weather resistance. This is because when the pKa of the light stabilizer is larger than 7.0, side reactions are likely to occur due to acid-base reactions near the remaining monomers, and the proportion of the light stabilizer in the top coat layer 2 is likely to decrease. To become. Therefore, it is preferable to use a light stabilizer with a pKa of 7.0 or less.

(Method for measuring pKa of photostabilizer)
A 1:1 acetonitrile:chloroform solution of 0.1N perchloric acid/dioxane was added dropwise to an organic reference substance having a known pKa value in an aqueous system, and the half-neutralization potential (HNP) in a non-aqueous system was titrated. At that time, a plot of HNP calibration curve against pKa was created. Next, the photostabilizer was titrated in the same manner, and the corresponding pKa was determined from the calibration curve plot.

(Method for measuring pKa of ultraviolet absorber when absorbing light)
Here, the ultraviolet absorber was dissolved in acetonitrile so that the absorbance at the maximum absorption wavelength was 1, and nitrogen was bubbled for 15 minutes. Thereafter, 70% perchloric acid was added dropwise to this solution to change the pH of the solution. At that time, the absorption spectrum of the solution was measured, and the amount of hydrogen ions added to the nitrogen of the ultraviolet absorber and the benzotriazole skeleton or triazine skeleton of the ultraviolet absorber at each pH was calculated from the absorbance at λmax. The pKa of the ultraviolet absorber at the time of light absorption was determined from the point where the values were equal. A Hitachi High-Tech U-4000 spectrophotometer was used to measure the absorption spectrum.

(pH measurement method of silica particles)
Measurements were carried out in accordance with JIS. First, 200 g of purified water is added to 10 g of silica particles that have been dried at 170° C. for 2 hours in the atmosphere, and the mixture is covered with a watch glass. Thereafter, the mixture was heated and stirred at 80±3° C. for 1 hour, and then cooled to room temperature and the supernatant liquid was collected. After the supernatant liquid was cooled to 25° C., it was measured using an analog pH meter HM-7J (manufactured by Toa DKK Co., Ltd.) in accordance with JIS Z8802.

Specific examples of the laminate and decorative sheet according to the present invention will be described below.
<Example 1>
For 100 parts by mass of highly crystalline homopolypropylene resin, 0.5 parts by mass of a hindered phenolic antioxidant (Irganox 1010; manufactured by BASF) and a triazine-based ultraviolet absorber (CYASORB UV-1164; manufactured by SUNCHEM). A resin containing 0.5 parts by mass of 0.5 parts by mass and 0.5 parts by mass of a NOR light stabilizer (Tinuvin XT850 FF; manufactured by BASF) was melt-extruded using an extruder to form a transparent high-temperature film with a thickness of 100 μm. A sheet-like transparent resin layer 3 as a crystalline polypropylene sheet was formed. Then, both surfaces of the obtained transparent resin layer 3 were subjected to corona treatment, and the wetting tension of the sheet surface was set to 40 dyn/cm or more.

On the other hand, a pattern was printed on one side of an 80 μm polyethylene sheet (original fabric layer 6) with hiding properties using a gravure printing method using a two-component urethane ink (V180; manufactured by Toyo Ink Co., Ltd.). A picture pattern layer 5a was provided, and the other surface of the original fabric layer 6 was coated with a primer.
After that, the transparent resin layer 3 is dry laminated on the surface of the picture pattern layer 5a of the original fabric layer 6 using a dry laminating adhesive (Takelac A540; manufactured by Mitsui Chemicals, Inc.; coating amount: 2 g/m2). Attached according to the law. An embossed pattern 3a was applied to the surface of the transparent resin layer 3 of this bonded sheet.
An example in which the top coat layer 2 was formed by applying and drying the following composition for forming a top coat layer to a transparent resin layer 3 having an embossed pattern 3a at a coating thickness of 3 g/m2, and having a total thickness of 185 μm. 1 decorative sheet 1 was obtained.

(Composition for forming top coat layer A)
The composition for forming top coat layer A was constructed by blending the following curing agent, gloss modifier, ultraviolet absorber, and light stabilizer into the following polymer solution A.
・Polymer solution A
80 g of methyl methacrylate and 20 g of 2-hydroxyethyl methacrylate were introduced into a four-neck flask equipped with a stirrer, a nitrogen inlet tube, and a reflux condenser, and 70 g of ethyl acetate was added and dissolved, and the mixture was placed in a nitrogen atmosphere on an oil bath. The mixture was stirred. Polymerization was started by adding 0.2 g of α,α'-azobisisobutyronitrile to this, and the mixture was heated and stirred for 5 hours on an oil bath at 60°C to form a colorless and viscous polymer solution A. I got it.
・Curing agent Product name: Duranate 24A-100
Blend: 5 parts by mass/gloss modifier (inorganic particles)
Product name: P-801 (manufactured by Mizusawa Chemical Industry Co., Ltd.)
Properties: irregular shape, average particle size 6.0 μm, pH 6.8
Formula: 10 parts by mass/UV absorber Product name: Tinuvin 329 (manufactured by BASF)
Blend: 2.5 parts by mass/light stabilizer
Product name: Tinuvin 123 (manufactured by BASF)
Blend: 1.5 parts by mass

<Example 2>
A decorative sheet 1 of Example 2 was obtained in the same manner as in Example 1 except that the gloss modifier of Example 1 was replaced with C-402 (Mizusawa Chemical Industry Co., Ltd.).
<Example 3>
A decorative sheet 1 of Example 3 was obtained in the same manner as in Example 1 except that the gloss modifier of Example 1 was replaced with NP-8 (Mizusawa Chemical Industry Co., Ltd.).

<Example 4>
A decorative sheet 1 of Example 4 was obtained in the same manner as in Example 1 except that the type of light stabilizer in Example 1 was changed to Tinuvin 152 (manufactured by BASF).
<Example 5>
A decorative sheet 1 of Example 5 was obtained in the same manner as in Example 2 except that the type of light stabilizer in Example 2 was changed to Tinuvin 152 (manufactured by BASF).

<Example 6>
A decorative sheet 1 of Example 6 was obtained in the same manner as in Example 3 except that the type of light stabilizer in Example 3 was changed to Tinuvin 152 (manufactured by BASF).
<Example 7>
A decorative sheet 1 of Example 7 was obtained in the same manner as in Example 1 except that the amount of light stabilizer in Example 1 was changed to 0.5 parts by mass.

<Example 8>
A decorative sheet 1 of Example 8 was obtained in the same manner as in Example 1 except that the amount of light stabilizer in Example 1 was changed to 3.0 parts by mass.
<Example 9>
A decorative sheet 1 of Example 9 was obtained in the same manner as in Example 1 except that the amount of light stabilizer in Example 1 was changed to 15.0 parts by mass.

<Comparative Examples 1 to 3>
Decorative sheets 1 of Comparative Examples 1 to 3 were obtained in the same manner as in Example 1 except that the light stabilizer in Examples 1 to 3 was replaced with Tinuvin 292 (manufactured by BASF).
<Comparative example 4>
A decorative sheet 1 of Comparative Example 4 was obtained in the same manner as in Example 1 except that the light stabilizer of Example 1 was not blended.

Table 1 shows the light stabilizers and gloss modifiers used. In addition, Table 1 also describes the evaluation results.

Further, based on Example 1, the following decorative sheets of Examples 10 to 18 were produced by changing the top coat layer.
<Example 10>
A decorative sheet of Example 10 was obtained, which consisted of a top coat layer B in which the top coat layer forming composition of Example 1 was changed as follows.
(Composition for forming top coat layer B)
The composition for forming top coat layer B was constructed by blending the following initiator, gloss modifier, ultraviolet absorber, and light stabilizer with the following resin liquid A.
・Resin liquid A
Product name: M405 (Toagosei)
・Initiator Product name: Irgcure184 (manufactured by BASF)
Blend: 5 parts by mass・Gloss adjuster (inorganic particles) Same as Example 1・Ultraviolet absorber Same as Example 1・Light stabilizer Same as Example 1

<Example 11>
A two-layer example in which a top coat layer C, which was the same as in Example 1 except that polymer solution A in Example 1 was replaced with polymer solution B, was coated on top coat layer A in Example 1. 11 decorative sheets were obtained. The method for preparing polymer solution B is described below.
・Polymer solution B
50 g of methyl methacrylate and 50 g of 2-hydroxyethyl methacrylate were introduced into a four-necked flask equipped with a stirrer, a nitrogen inlet tube, and a reflux condenser, and 70 g of ethyl acetate was added and dissolved, and the mixture was placed in a nitrogen atmosphere on an oil bath. The mixture was stirred. Polymerization was started by adding 0.2 g of α, α'-azobisisobutyronitrile to this, and the mixture was heated and stirred for 5 hours on an oil bath at 60°C to form a colorless and viscous polymer solution B. I got it.

<Example 12>
Top coat layer B used in Example 10 was coated on top coat layer A of Example 1 to obtain a decorative sheet of Example 12 consisting of two layers.

<Example 13>
A decorative sheet of Example 13 was obtained, which consisted of a top coat layer D in which the top coat layer forming composition of Example 1 was changed as follows.
(Composition for forming top coat layer D)
The composition for forming top coat layer D was constructed by blending the following curing agent, initiator, gloss adjuster, ultraviolet absorber, and light stabilizer into the following resin liquid B.
・Resin liquid B
Resin liquid B was obtained by blending 50 parts by mass of polymer liquid A and resin liquid A.
・Initiator Product name: Irgcure184 (manufactured by BASF)
Blend: 5 parts by mass / Curing agent Product name: Duranate 24A-100
Blend: 5 parts by mass・Gloss adjuster (inorganic particles) Same as Example 1・Ultraviolet absorber Same as Example 1・Light stabilizer Same as Example 1

<Example 14>
Top coat layer D used in Example 13 was coated on top coat layer A of Example 1 to obtain a decorative sheet of Example 14 consisting of two layers.

<Example 15>
On the top coat layer D of Example 13, a top coat layer E of the composition for forming a top coat layer of Example 13 with the following modifications was coated to obtain a decorative sheet of Example 15 consisting of two layers.
(Composition for forming top coat layer E)
The composition for forming top coat layer E was composed of the following resin liquid C mixed with the following curing agent, initiator, gloss adjuster, ultraviolet absorber, and light stabilizer.
・Resin liquid C
Resin liquid C was obtained by blending 20 parts by mass of polymer liquid B and 80 parts by mass of resin liquid A.
・Initiator: Same as Example 10 ・Curing agent: Same as Example 10 ・Gloss adjuster (inorganic particles): Same as Example 1 ・Ultraviolet absorber: Same as Example 1 ・Light stabilizer: Same as Example 1

<Example 16>
Top coat layer B used in Example 10 was coated on top coat layer D of Example 13 to obtain a decorative sheet of Example 16 consisting of two layers.
<Example 17>
The coats used in Example 13 and Example 10 were sequentially laminated on the top coat layer of Example 1 to obtain a decorative sheet of Example 17 consisting of three layers.
<Example 18>
The coating used in Example 10 was applied on the top coat layer of Example 11 to obtain a decorative sheet of Example 18 consisting of three layers.

Table 2 shows the layer structure of the top coat layer of Example 1 and Examples 10 to 18, and the light stabilizer and gloss modifier used. In addition, Table 2 also describes the evaluation results.
Here, in the layer structure, "thermal" represents a thermosetting layer, "UV" represents a photocuring layer, and "UV/thermal" represents a mixed layer of a photocuring resin and a thermosetting resin.

<Evaluation>
(Weather resistance (appearance))
The decorative sheets obtained in the Examples and Comparative Examples were set in Metal Weather manufactured by Daipura Wintes Co., Ltd. and exposed for 20 hours under light conditions (illuminance: 60 mW/cm2, black panel temperature 63°C, layer humidity 50% RH). , Weather resistance test in which the test is left for 4 hours under dew condensation conditions (illuminance: 0 mW/cm2, black panel temperature 30℃, layer humidity 98% RH), and for 500 or 1000 hours under water spray conditions (10 seconds before and after dew condensation conditions). I did it. After the above test, the board was held for 2 days at 25° C. and 50% RH, and the appearance of the board surface, such as cracks and yellowing, was visually evaluated according to the following criteria.

(Appearance of paint film)
○: There was no change in appearance at all.
△: There were fine cracks on the surface.
×: There were numerous cracks on the surface.
(Base material yellowing)
○: There was no change in appearance at all.
Δ: Slight yellowing was observed.
×: Significant yellowing.

As shown in Table 1, in the decorative sheet of each example, by blending the resin with a light stabilizer with a pKa of 4.0 to 7.0, the gloss after the weathering test was improved without causing haze. It was possible to produce a decorative sheet that was able to suppress the degree change and was also less susceptible to change in appearance.
As can be seen from Tables 1 and 2, when a light stabilizer with a pKa greater than 7.0 is added to the surface protective layer, both the appearance of the coating film and the yellowing of the base material decrease from pKa of 4.0. It was worse compared to the case where a light stabilizer of 7.0 was used. Further, when 15.0 parts by mass of a light stabilizer was blended, haze occurred in the coating film at the time of production, but no change in appearance or yellowing of the resin was observed before and after the weather resistance test. This is because the ultraviolet absorber and light stabilizer bleed out onto the surface protective layer, resulting in a high haze value, but it is thought that the performance was achieved because sufficient weathering agent was included.

From the above results, it can be seen that the decorative sheet 1 of the example based on the present invention has excellent weather resistance.
Note that the decorative sheet 1 of the present invention is not limited to the above-described embodiments and examples, and various changes can be made without impairing the characteristics of the invention.

1 Decorative sheet 2 Top coat layer 3 Transparent resin layer 3a Embossed pattern 4 Adhesive layer 5 Ink layer 5a Picture pattern layer 5b Solid ink layer 6 Original fabric layer (base material layer)
7 Adhesive resin layer

Claims (8)

A laminate consisting of a plurality of resin layers,
The top coat layer located on the outermost surface side of the laminate contains a light stabilizer having a pKa of 4.0 to 7.0,
The top coat layer includes a thermosetting layer and a photocuring layer,
The thermosetting layer contains more ultraviolet absorber than the photocuring layer,
The laminate , wherein the ultraviolet absorber is acidic and has a pKa of -4.5 to -5.5 when irradiated with light . The laminate according to claim 1, wherein the light stabilizer is a hindered amine light stabilizer. 3. The laminate according to claim 1, wherein the top coat layer contains a gloss modifier made of inorganic particles. 4. The laminate according to claim 3, wherein the inorganic particles have a pH greater than 5.0 and less than 8.5 when dispersed. 5. The laminate according to claim 3, wherein the gloss modifier is polydimethylsiloxane, polyethylene wax, or inorganic particles surface-modified with a surfactant. The main component of the resin is an olefin resin, and the resin layer has an olefin resin layer containing 0.3 parts by mass or more of a compound with a pKa of 7.0 or less based on 100 parts by mass of the resin material,
The laminate according to any one of claims 1 to 5, wherein the top coat layer is formed on the olefin resin layer. The thermosetting resin constituting the thermosetting layer is a resin containing methyl methacrylate and 2-hydroxyethyl methacrylate as constituent components. laminate. A decorative sheet comprising the laminate according to any one of claims 1 to 7.

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